1. Field of the Invention
The present invention relates to an image forming apparatus equipped with a media bucket for accommodating a photosensitive sheet cartridge provided with a supply shaft for delivering a photosensitive sheet, and a take-up shaft for taking up the photosensitive sheet after use. The photosensitive sheet cartridge will hereinafter be called the "cartridge".
2. Description of the Prior Art
Japanese Laid-Open Patent Publication No.58-88739 discloses a method of forming an image by using a photosensitive sheet coated with microcapsules containing photosetting materials and image forming agent and an image receiving sheet coated with a developer that reacts with the image forming agent to develop colors. When the photosensitive sheet is exposed to light, the microcapsules are caused to harden on light-hit spots, thereby forming a latent image on the photosensitive sheet. When the image receiving sheet is superposed over the latent image and pressed together by a press roller unit, unhardened microcapsules rupture and enable the image forming agent contained therein to flow out and react with the developer to develop colors, thereby forming a colored image on the image receiving sheet.
This conventional image forming method is provided with a cartridge for accommodating the photosensitive sheet in a roll form so as to protect the microcapsules from being subjected to accidental exposure to light or rupturing before the expected exposure.
Where the cartridge is provided, a bucket is slidably mounted in the image forming apparatus so as to facilitate the mount and dismount of the cartridge. The bucket is drawn, and an exposure plate fixed thereto by means of fasteners such as screws, is removed so as to load a cartridge in the bucket. Then, the exposure plate is returned to the bucket and fixed thereto by means of screws, etc. A top portion of the photosensitive sheet is pulled from the cartridge over the exposure plate so as to make it ready for automatic delivery into a feed path. Finally, the bucket is inserted into the image forming apparatus.
The conventional method is disadvantageous in that the dismount and mount of the bucket involves a complicated and labor-consuming task which consists of drawing the bucket, removing the exposure plate, loading the cartridge, returning the exposure plate, setting the photosensitive sheet, and mounting the bucket again. During the work small accidents often happen such as losing screws, accidentally breaking the cartridge, and entangling the photosensitive sheet.